The Mummy no match for Batman
Starring Brendan Fraser, the movie went straight in at number two, having made some £2.9 million during its opening weekend.
However, The Dark Knight still sits at the top for the third week, with takings of more than £4 million.
After an underwhelming first week, the new X-Files film has now slipped back to tenth place.
Batman is refusing to be toppled, with X-Files star Gillian Anderson blaming her film's poor performance on the huge success of The Dark Knight.
Abba musical Mamma Mia has slipped down to third place, but is still the biggest earner in the top ten overall, having made £37.7 million during its five weeks of release.
Animated adventure WALL-E and teen dance movie Make It Happen complete the top five, standing at four and five respectively.
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